Batteries are used in various fields, for example, electronic devices such as a mobile phone and a personal computer, vehicles such as a hybrid car and an electric car. For example, a battery used in a vehicle field is configured such that a power generating element is enclosed in a casing of a can body and a lid member is welded to an opening of the casing to seal the opening. The lid member is formed with a through hole penetrating therethrough in a thickness direction of the lid member to allow an insert-through part of a collector terminal member electrically connected to the power generating element extends out through the through hole.
A method for fixing the collector terminal member to the lid member is disclosed as a technique, for example disclosed in Patent Document 1, that an insert-through part of a cylindrical collector terminal member is inserted through openings formed one each in an external connecting terminal, an insulator, the lid member, and a gasket, and an upper end of the insert-through part is deformed or riveted to extend radially outward relative to the center axis of the insert-through part, providing temporary joining, and further the extended upper end of the insert-through part and an upper surface of the external connecting terminal are welded and fixed to each other. In the battery disclosed in Patent Document 1, the gasket seals between the lid member and the collector terminal member to suppress gas leakage from the opening of the lid member.